1. Field of the Invention
The invention relates to apparatus for recording data regarding the operation of a sea borne vessel. More particularly, the invention relates to apparatus for recording and protecting data leading up to an accident or xe2x80x9cincidentxe2x80x9d.
2. Brief Description of the Prior Art
It has long been noted that the investigation of maritime accidents and incidents could benefit from the recording of data and audible commands occurring aboard ships. Indeed, many considered this an inevitable technological extension of the time-honored ship""s logbook. This desire has culminated in the development of an international standard governing the performance of a Voyage Data Recorder (VDR).
In 1974 the Safety of Life at Sea (SOLAS) Convention of the International Maritime Organization (IMO) acknowledged the value and expressed the desire of having recorders on ships similar to the xe2x80x9cblack boxxe2x80x9d flight recorders for aircraft. This began a long process of establishing international standards and requirements for a Voyage Data Recorder (VDR).
In 1996, VDR requirements, which had been debated for a long time, began to emerge in the navigation and electronics subgroup (NAV) of the IMO. Anticipating an eventual IMO resolution concerning VDRs, IEC (International Electrotechnical Commission) TC80 formed WG11, which began structuring a specification based on preliminary drafts of the NAV requirements. The IMO passed resolution A. 861 (20) in November 1997 and the IEC standard 61996 was completed as a Committee Draft for Voting in March 1999. The specification was published in August 2000.
The IEC 61996 Ship borne Voyage Data Recorder Performance Requirements describes data acquisition and storage functions and refers to a xe2x80x9cprotective capsulexe2x80x9d and a xe2x80x9cfinal storage mediumxe2x80x9d. Architecture for complying with this standard has emerged with two major components.
In the first component, the ship""s interfaces, data acquisition, and soft recording functions are encompassed in a Data Management Unit (DMU). The DMU is intended for installation in the relatively benign environment of the bridge. The second component is the Hardened Voyage Recorder (HVR) which encompasses the protective capsule and final storage medium. The HVR is designed for survivability and recoverability. It is intended for external installation on the bridge deck or on top of the superstructure.
The primary function of the Hardened Voyage Recorder (HVR) is to protect the data acquired by the Voyage Data Recorder (VDR) so that the data can be used during accident or xe2x80x9cincidentxe2x80x9d investigation.
It is therefore an object of the invention to provide a Hardened Voyage Recorder which meets or exceeds the requirements of the IEC 61996 test specifications, for the protective capsule and final storage medium.
It is also an object of the invention to provide a Hardened Voyage Recorder which has a substantial storage capacity.
It is another object of the invention to provide a Hardened Voyage Recorder which is capable of recording radar data, audio, and other sensor data.
It is yet another object of the invention to provide a Hardened Voyage Recorder which has a long life and low operating power.
It is another object of the invention to provide a Hardened Voyage Recorder which is easy to install and service.
It is still another object of the invention to provide a Hardened Voyage Recorder which easily interfaces with one or more DMUs.
In accord with these objects which will be discussed in detail below, the Hardened Voyage Recorder (HVR) according to the invention includes two separable subassemblies.
The first subassembly is a mounting base subassembly designed to be directly fastened to the ship and provide a watertight cable entry for power and data connections.
The second subassembly is a removable hardened memory subassembly which is attached to the mounting base with a quick releasing clamp. The hardened memory subassembly has a bracket for an externally mounted underwater location beacon with dual activation moisture sensors to avoid inadvertent activation due to spray, rain, or hosing off. The HVR is preferably painted a highly visible florescent orange with white reflective labels. The reflective labels contain the required text: VOYAGE DATA RECORDER, DO NOT OPEN, REPORT TO AUTHORITIES.
The mounting base subassembly includes electronics for receiving data and writing data to the memory in the hardened memory subassembly.
According to the presently preferred embodiment, the power connection accepts either 110/220 VAC or 24 VDC and the data connection is an ETHERNET connection. The AC and DC power connections may both be active at the same time. The AC connection is preferably used during normal conditions and the DC connection is preferably coupled to the ship""s UPS (uninterrupted power supply).
Further, according to the presently preferred embodiment, the HVR receives data via TCP/IP (terminal connection protocol/internet protocol) over ETHERNET. The HVR is therefore assigned an IP address and is configurable via a xe2x80x9cweb browserxe2x80x9d. This also enables the formation of a network of multiple HVRs all coupled to numerous sensors via the ETHERNET network.
The removable hardened memory subassembly preferably includes 1.5 gigabytes of solid state memory which is protected in a xe2x80x9cboilerxe2x80x9d such as that disclosed in co-owned, co-pending application Ser. No. 09/899,646 filed Jul. 6, 2001, the complete disclosure of which is hereby incorporated herein by reference.